If you change it to drive over 4 days, Trippy gives you a good starting point: https://www.trippy.com/drive/Tampa-to-Columbia-MO-over-4-days From there, you can adjust the overnights and add or remove stops, but it actually might make sense to drive a bit farther the first day, then take your time over the next 3 days. Have a great trip!
I would drive from Tampa,FL to Biloxi, MS. I would drive from Biloxi to Gold Strike Casino&Hotel in Tunica, MS. I would drive from there to Columbia, MO. You can use Hotwire.com to make reservations as you travel when you reach your 300 mile limit. I would not drive through Atlanta.